Instructional Videos

Containers for Tree Seedlings: Forest and Conservation Nurseries

In this virtual forestry field day, Dr. J.B. Friday, CTAHR Extension Forester, visits four nurseries on Hawai'i Island to examine proper containers for forestry and conservation projects in Hawaii and other Pacific Islands.

Native Forest Tree Seed: Collecting, Processing and Storage

In this forestry field day, Jill Wagner, owner of Future Forests Nursery and Director of the Hawaii Island Native Seed Bank joins Dr. J.B. Friday to demonstrate how to clean, dry, and package native plant seed for long term storage by Pacific island nurseries.

Improving Form of Young Koa Trees: Pruning and Singling to Improve Timber Quality

Most planted koa trees are branchy and forked. Although this is not a problem if you just want bird habitat, these trees are useless for producing koa timber. In koa plantations, the leaders on the young trees are often killed by insects, cattle, rust, or just damaged by the wind. Once the leader is killed, several of the branches compete to produce a new leader, and the result is the typical multi-stemmed tree. Koa has weak apical dominance, so one leader is unable to suppress the others, as it would do in some other tree species.

Pruning of koa branches with a saw once they become woody usually permanently damages the tree and introduces rot. Koa does not compartmentalize infections well. When the branches are young, however, they can be clipped off with a pair of clippers, as long as they are the size of a pencil or smaller. By clipping off all but one of the multiple leaders, a process called “singling”, foresters can save a tree from becoming multiple-stemmed. This quick procedure can greatly improve the tree’s future potential to become timber.